1. Rubidium has 2 isotopes in nature, and the average atomic mass is 85.557 amu. Rb-85 has a relative abundance of 72.15%.
What is the relative abundance of the other isotope, Rb-87?

Sodium nitrite (nano2) reacted with 2−iodooctane to give a mixture of two constitutionally isomeric compounds of molecular formula c8h17no2 in a combined yield of 88%. draw reasonable structures for these two isomers. click the "draw structure" button to launch the drawing utility. place the two compounds in the appropriate boxes below.

The yearly amounts of carbon emissions from cars in belgium are normally distributed with a mean of 13.9 gigagrams per year and a standard deviation of 5.8 gigagrams per year. find the probability that the amount of carbon emissions from cars in belgium for a randomly selected year are between 11.5 gigagrams and 14.0 gigagrams per year. a. 0.340 b. 0.660 c. 0.167 d. 0.397

At 20°c, a sample of h2o liquid and a sample of co2 gas each have the same average kinetic energy. why is one a liquid and the other a gas at this temperature?